Burglar-alarm



(No Model.)

T. JAMES, Jr.

BURGLAR ALARM. u, l No. 328,225. Patented Oct. 13, 1885.

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NITED STATES PATENT Ottica THOMAS JAMES, JR., OF CARLYLE, ILLINOIS.

BURGLAR-ALARM.

SPECIFICATION forming part of Letters Patent No. 328,225, dated October 13, 1885.

Application filed June 18, 1885. SeralNo.169,06tl. `(No model.)

.To all whom, it may concern.-

Be it known that l, THOMAS JAMES, Jr., a

citizen of the United States, residing at Carlyle, in the county of Ulinton and State of Illinois, have invented certain new and useful Improvements in Burglar-Alarms; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled inthe art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification. This invention relates to an improved burglar-alarm; and it consists in the construction, combination, and arrangement of the several parts hereinafter described, and point-ed out in the claim.

In the drawings, Figure l shows my device secured to thejamb of a door or other support, with the hammer raised into position to be struck by the door, window, or transom when the latter is opened. Fig. 2 shows the hammer down. Fig. 3 is a detail of the supporting-arm or main bar, and Fig. 4: is a detail of the hammer.

In Fig. 1 I show a door-jamb, A, and apor tion of adoor,B, the latter being closed against the jamb. My improved device is screwed into the jamb and the hammer is raised into position to be struck and knocked down by the door when the latter is opened.

a is the supporting-arm or main bar, provided with a threaded shank, a', adapted to be screwed into the door-jamb.

Near the outer end of the arm an opening, a2, is provided to receive the cartridge or cap b. A longitudinal slot, c3, is madein the rear end of the arm,through which the lower end of the hammer projects. Lugs at a4 are formed on opposite sides of the slot a3, in which the hammer is pivoted.

A spring, c, is placed on the under side of the arm, and has its outer end secured thereto near the cartridgeopening a2. Its inner end A nose, d2, is projected from the outer end of the arm and adapted to strike the cap or cartridge b. The end of the nose di is so formed as to have one portion ot' the end thereof rest on the arm, while the other portion extends over the cap-opening a. This gives a tirm grip on the cap or cartridge, and at the same time prevent-s the nose from being driven downward into the opening.

The rear end of the arm is provided with an extension, d3, beyond its pivot,whiclr impinges on the inner end of the supporting-spring c. The extension is slightly curved downward, and is provided with straight bearingedges d* The spring bears against the edge d* when the hammer is raised, as in Fig. l, and against the edge d5 when the hammer is down. These straight bearing-edges afford means for giving greater steadiness to the arm in the two positionsjust referred to. If the end of the extension were a continuous curve, the arm could be knocked down too easily, or could be raised too easily. Vhen made, as shown, the danger of accidental discharges is reduced to a minimum.

I have shown lugs c as a means for connecting the hammer to the arm. The lugs could be dispensed with and the pivot-pin be arranged in openings formed in the body ofthe arm. I prefer to form the lugs, as shown, though I do not limit myself to them.

The operation of the device is apparent. The cartridge or cap is placed in the capopening. The shank of the arm is screwed into thejamb of the door, so that the hammer, when raised,\vill project overthe track of the door. The door,when it is opened,strikes and knocks down the hammer, and the nose strikes and explodes the cartridge. I here provide a Very compact burglar-alarm which may be carried in the vest-pocket.

I have described my device as having a threaded shank which may be screwed into the wood. This is the most convenient means of attaching to the wood; but it will be understood that the shank could be made tlat and arranged at right angles to the main arm and perforated to receive a screw or nail which could be driven into the wood. The shank, as shown in the drawings, instead of being threaded could be made smooth, so that it could be driven into the wood.

The device can be arranged by a transom, or

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by a Window which swings on hinges. The hammer is provided with a loop or eye on its outer end, to which a string may be attached. By means of this I can arrange the device anywhere and carry the string across the room, so that the foot of a passing person will strike it and pull the hammer down, or by the raising ofa window the hammer may bethrown down.

The relative position of the parts could be reversed. The slot in the bar could be at the outer end and the cap-opening at the inner end, and such an arrangement would answer where the hammer is to be set off by cords, &c. I prefer to make it in the particular form shown.

Again, while I prefer to pivot the hammer in the slot7 as shown, the parts could be so constructed that the hammer could be pivoted on the side ofthe main bar and bentlaterally sufficiently to strike the cap or cartridge supported in an opening or other support adapted for the purpose.

Having thus described myinvention, what I claim, and desire to secure by Letters Patent, is-

The herein shown and describedburglaw alarm, consisting of the following elements in combination: a main bar terminating in a shank at one end and perforated at its other end to receive the cartridge, longitudinally slotted near the shank and provided with lugs on either side of the slot, the hammer pivoted between thelugs,its rear end extending within and beyond the slot and havingstraight bearing-edges having a nose, the face of which is adapted to rest partially on the main bar and is extended partially over the cartridge-receiving aperture, and a spring fastened to the under side of the main bar and arranged to engage and bear upon one of the straight edges ofthe end extension of the hammer, as and for the purposes set forth.

In testimony whereof I affix my signature in presence of two Witnesses.

THOMAS JAMES, JR.

Vitnesses:

HENRY BENDER, HENRY Hnss. 

